Rue, Ruta. A small perennial shrub which is native to the southern countries of Europe. It grows to four or five feet and its leaves are thick, fleshy, divided, and blue-green. The yellow flowers which appear in June are without beauty: they grow in cymes at the tips of the branches. The seeds, which are small, black, and angular, are enclosed in capsules, each of which has five locules. Although the foliage of this shrub is attractive, it has such a powerful and repugnant smell that it can scarcely be enjoyed. It grows rapidly in any soil, is hardy, and propagates readily from seed, layers, and even cuttings, this last method being the quickest.

Rue has several medicinal properties, notably that of being an antidote. Field marshals use it for curing diseased horses or livestock. In England, Holland, and Germany rue is used in a number of stews. In Italy the young shoots are eaten in salads. However, in France this plant is not used in cooking: tastes, like mores and opinions, vary from country to country.

There are several known species of rue, of which the following are the most striking.

1. Garden rue: this is the commonest rue, of which the greatest use is made. [1]

2. Small-leaved garden rue: the leaves and flowers of this rue are smaller than those of garden rue. This shrub has no other distinguishing features.

3. Garden rue with small, variegated leaves: the leaves of this rue have attractive white stripes in winter and at the beginning of spring. Remarkably, these stripes are visible only when the sap is no longer flowing. They disappear gradually as the shrub vegetates in spring, and reappear in autumn as soon as the sap has stopped flowing. This plant is in effect a plant barometer.

5. Aleppo broad-leaved rue: this rue is more delicate than those described above, and exhales an even stronger and more unpleasant odour.

6. Large, wild rue: although this rue closely resembles the first species, it grows taller, its leaves, flowers, and seeds are smaller, and its foliage is whiter. However, it is less hardy, and its smell is so strong and unbearable that it goes to one’s head. This plant has an agent which is so active and penetrating that it causes dermatitis when one touches the leaves. [2]

7. Small, wild rue: this rue grows much shorter than large wild rue, its leaves and flowers are smaller, and it is in no way superior.

8. Spanish rue: this rue is tender; its leaves resemble those of flax.

Notes

1. Ruta graveolens, or ‘herb of grace’. There are eight species of rue: they are listed in Huxley et al., 1992, iv. 152.

2. The sap of rue contains furanocoumarins (ibid.).